Retinoids are a class of compounds related to Vitamin A. Retinoids serve many functions in the body such as, cell turnover, growth and renewal, epithelial cell differentiation, vision, bone growth, and collagen formation. Medicinally, retinoids are commonly used in drug applications to treat acne, psoriasis, and skin cancer. More recently, retinol has been used cosmetically in skin anti-aging products mostly because of cell turnover and renewal properties.
Although retinoids are attractive for drug and cosmetic applications, they suffer from a serious drawback. They are unstable to normal room light and oxygen. A variety of techniques for stabilizing retinoids have been tried. In one type of approach, the terminal —OH group of retinol is esterified with various acids from acetic acid to palmitic acid. Although stability of the esterified product is generally better than the parent compound, the biological efficacy is typically decreased. BASF markets a stabilized retinol preparation of a 50% retinol mixture containing vitamins C and E, and the antioxidants butylatedhydroxytoluene and butylatedhydroxyanisole under the name RETISTAR.
The production of products containing retinoids is typically carried out under yellow light and a blanket of inert gas, most often nitrogen or argon, to preserve the retinoid. This considerably increases the cost of production of retinoid containing products. When the customer or patient opens the jar or tube of a product containing a retinoid, decomposition of the retinoid begins as a result of exposure to oxygen and light, and the drug or cosmetic is rendered ineffective in a matter of weeks or a few months at best.